Articles de revues : « Photon addition »

1

Walker, J. G. « Sub-poissonian Photon Statistics by Photon Addition ». Optica Acta : International Journal of Optics 33, n^o 3 (mars 1986) : 213–18. http://dx.doi.org/10.1080/713821940.

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2

Hoai, Nguyen Thi Xuan, et Truong Minh Duc. « Nonclassical properties and teleportation in the two-mode photon-added displaced squeezed states ». International Journal of Modern Physics B 30, n^o 07 (18 mars 2016) : 1650032. http://dx.doi.org/10.1142/s0217979216500326.

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In this paper, we study the nonclassical properties and find out the effect of photon addition on these properties as well as the process of teleportation in the two-mode photon-added displaced squeezed (TMPADS) states. We derive the analytic expressions of the Wigner function, the photon number distribution and the intermode photon antibunching for these states. We show that photon addition operation not only makes the Wigner function become negative but also leads to increase the degree of antibunching. The peak of the photon number distribution becomes flatter and shifts to the greater number of photons by adding photons to both modes simultaneously. Furthermore, it is proved that the degree of intermodal entanglement becomes bigger and bigger through increasing the number of photons added to both modes. As expected, when using these states as an entanglement resource to teleport a state, the average fidelity of teleportation process is also improved by increasing the number of added photons.

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3

Filippov, S. N. « On Quantum Operations of Photon Subtraction and Photon Addition ». Lobachevskii Journal of Mathematics 40, n^o 10 (octobre 2019) : 1470–78. http://dx.doi.org/10.1134/s199508021910010x.

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Jang, Jae-Young, et Myungjin Cho. « Lensless Three-Dimensional Imaging under Photon-Starved Conditions ». Sensors 23, n^o 4 (20 février 2023) : 2336. http://dx.doi.org/10.3390/s23042336.

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In this paper, we propose a lensless three-dimensional (3D) imaging under photon-starved conditions using diffraction grating and computational photon counting method. In conventional 3D imaging with and without the lens, 3D visualization of objects under photon-starved conditions may be difficult due to lack of photons. To solve this problem, our proposed method uses diffraction grating imaging as lensless 3D imaging and computational photon counting method for 3D visualization of objects under these conditions. In addition, to improve the visual quality of 3D images under severely photon-starved conditions, in this paper, multiple observation photon counting method with advanced statistical estimation such as Bayesian estimation is proposed. Multiple observation photon counting method can estimate the more accurate 3D images by remedying the random errors of photon occurrence because it can increase the samples of photons. To prove the ability of our proposed method, we implement the optical experiments and calculate the peak sidelobe ratio as the performance metric.

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5

Melde, T. « A photon number density operator in the covariant formulation of quantum electrodynamics ». Canadian Journal of Physics 77, n^o 3 (1 juillet 1999) : 167–75. http://dx.doi.org/10.1139/p99-018.

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We introduce a new photon number density operator in the Gupta-Bleuler quantized photon field and show that the corresponding total number operator counts transverse photons in the new model. It is also shown that the suggested operator interpreted in the usual Hilbert space counts, in addition, a number of gauge photons for the free field. In the case of two fixed charges it also counts an extra number of scalar photons due the charges.PACS Nos.: 12.20.-m, 14.70.Pw, 42.50.Ar

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6

Sivakumar, S. « Truncated Coherent States and Photon-Addition ». International Journal of Theoretical Physics 53, n^o 5 (5 janvier 2014) : 1697–709. http://dx.doi.org/10.1007/s10773-013-1967-7.

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Nomerotski, A., M. Chekhlov, D. Dolzhenko, R. Glazenborg, B. Farella, M. Keach, R. Mahon, D. Orlov et P. Svihra. « Intensified Tpx3Cam, a fast data-driven optical camera with nanosecond timing resolution for single photon detection in quantum applications ». Journal of Instrumentation 18, n^o 01 (1 janvier 2023) : C01023. http://dx.doi.org/10.1088/1748-0221/18/01/c01023.

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Abstract We describe a fast data-driven optical camera, Tpx3Cam, with nanosecond scale timing resolution and 80 Mpixel/sec throughput. After the addition of intensifier, the camera is single photon sensitive with quantum efficiency determined primarily by the intensifier photocathode. The single photon performance of the camera was characterized with results on the gain, timing resolution and afterpulsing reported here. The intensified camera was successfully used for measurements in a variety of applications including quantum applications. As an example of such application, which requires simultaneous detection of multiple photons, we describe registration of photon pairs from the spontaneous parametric down-conversion source in a spectrometer. We measured the photon wavelength and timing with respective precisions of 0.15 nm and 3 ns, and also demonstrated that the two photons are anti-correlated in energy.

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Kosson, D. Sc, Robert L. « The effect of gravitational field on photon frequency:a fresh look at the photon ». Physics & ; Astronomy International Journal 6, n^o 1 (9 mars 2022) : 28–29. http://dx.doi.org/10.15406/paij.2022.06.00246.

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The purpose of this paper is to present a new description of the photon. The photon is postulated to be a rotating dipole, consisting of two masses, one with a positive charge and the other a negative charge. This conceptualization of the photon permits a parsimonious explanation of both the wave and particle properties of light while providing a straightforward hypothesis for the increased red shift associated with the early stages of the universe. In addition, if measurements could be made of the red shift associated with photons being drawn into a black hole, such measurements might aid in estimating the strength of the associated gravitational gradient.

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Stumpf, H. « Simultaneous Formation of Electric and Magnetic Photon States by Electroweak Symmetry Breaking ». Zeitschrift für Naturforschung A 59, n^o 4-5 (1 mai 2004) : 185–95. http://dx.doi.org/10.1515/zna-2004-4-501.

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In order to describe the electromagnetic effects (fields) of simultaneously occurring electric and (hypothetical fermionic) magnetic monopoles, Cabibbo and Ferrari introduced in addition to the conventional electric vector potential a magnetic vector potential, thus leading to electric and magnetic photons. A theoretical confirmation (and justification) of this phenomenological ansatz is provided by the manifold of photon states in de Broglie’s theory of fusion. Lochak showed that in this theory either electric or magnetic photon states can be derived. To study the possibility of the simultaneous existence of electric and magnetic photon states a modern version of de Broglie’s fusion theory is used, which is formulated by means of generalized de Broglie-Bargmann-Wigner equations. It is demonstrated that the corresponding photon equations admit the simultaneous existence of electric and magnetic photon states if the electroweak SU(2)- and CP-symmetry breakings are introduced into these equations. The latter symmetry violations induce violations of the permutation symmetry, which is crucial for the proof of Cabibbo’s and Ferrari’s hypothesis referred to photons with partonic substructure.

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10

Yeo, Gilsu, et Myungjin Cho. « Three-Dimensional Digital Zooming of Integral Imaging under Photon-Starved Conditions ». Sensors 23, n^o 5 (28 février 2023) : 2645. http://dx.doi.org/10.3390/s23052645.

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In this paper, we propose new three-dimensional (3D) visualization of objects at long distance under photon-starved conditions. In conventional three-dimensional image visualization techniques, the visual quality of three-dimensional images may be degraded because object images at long distances may have low resolution. Thus, in our proposed method, we utilize digital zooming, which can crop and interpolate the region of interest from the image to improve the visual quality of three-dimensional images at long distances. Under photon-starved conditions, three-dimensional images at long distances may not be visualized due to the lack of the number of photons. Photon counting integral imaging can be used to solve this problem, but objects at long distance may still have a small number of photons. In our method, a three-dimensional image can be reconstructed, since photon counting integral imaging with digital zooming is used. In addition, to estimate a more accurate three-dimensional image at long distance under photon-starved conditions, in this paper, multiple observation photon counting integral imaging (i.e., N observation photon counting integral imaging) is used. To show the feasibility of our proposed method, we implement the optical experiments and calculate performance metrics, such as peak sidelobe ratio. Therefore, our method can improve the visualization of three-dimensional objects at long distances under photon-starved conditions.

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Abdullah, Nzar Rauf, Chi-Shung Tang, Andrei Manolescu et Vidar Gudmundsson. « Manifestation of the Purcell Effect in Current Transport through a Dot–Cavity–QED System ». Nanomaterials 9, n^o 7 (17 juillet 2019) : 1023. http://dx.doi.org/10.3390/nano9071023.

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We study the transport properties of a wire-dot system coupled to a cavity and a photon reservoir. The system is considered to be microstructured from a two-dimensional electron gas in a GaAs heterostructure. The 3D photon cavity is active in the far-infrared or the terahertz regime. Tuning the photon energy, Rabi-resonant states emerge and in turn resonant current peaks are observed. We demonstrate the effects of the cavity–photon reservoir coupling, the mean photon number in the reservoir, the electron–photon coupling and the photon polarization on the intraband transitions occurring between the Rabi-resonant states, and on the corresponding resonant current peaks. The Rabi-splitting can be controlled by the photon polarization and the electron–photon coupling strength. In the selected range of the parameters, the electron–photon coupling and the cavity-environment coupling strengths, we observe the results of the Purcell effect enhancing the current peaks through the cavity by increasing the cavity–reservoir coupling, while they decrease with increasing electron–photon coupling. In addition, the resonant current peaks are also sensitive to the mean number of photons in the reservoir.

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Wang, Shuai, Hong-yi Fan et Li-yun Hu. « Photon-number distributions of non-Gaussian states generated by photon subtraction and addition ». Journal of the Optical Society of America B 29, n^o 5 (26 avril 2012) : 1020. http://dx.doi.org/10.1364/josab.29.001020.

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13

Chandra, N., et R. Ghosh. « Generation of entanglement between spin of an electron and polarization of a photon ». Quantum Information and Computation 9, n^o 1&2 (janvier 2009) : 36–61. http://dx.doi.org/10.26421/qic9.1-2-3.

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This paper shows an electron and a photon, emitted in two consecutive steps from an atom following the absorption of a single photon, may be entangled in the presence of the spin-orbit interaction only. This entanglement strongly depends upon the polarization of the absorbed and of the radiated photons, kinematics of two emitted particles, and dynamics of photoionization; however, the photoemission dynamics plays no role in this entanglement. This hybrid entanglement can be used in teleporting a quantum state encoded in a flying/stationary material particle onto a light pulse, or vice versa. Such an electron-photon entanglement, in addition, will make it possible to learn about the polarization of a single photon or spin-polarization of a free electron without making any measurements on the corresponding particle itself.

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Haug, Espen Gaarder. « Planck Speed : the Missing Speed of Physics ? Absolute Still Without Breaking Lorentz Symmetry ! » European Journal of Applied Physics 4, n^o 1 (8 janvier 2022) : 11–18. http://dx.doi.org/10.24018/ejphysics.2022.4.1.144.

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Today, the speed of light is one of the cornerstones of modern physics. It is the maximum speed limit for transferring information, and plays a very central role in relativity theory. It also seems to be the same as the assumed and measured speed of gravity (gravitons and/or gravitational waves). We are not questioning the speed of light, as we indeed think it is the maximum speed limit and that it is identical to the speed ofgravity, but we also think photons lead us to a second speed limit, which we will term the Planck speed. Photon-photon collisions are part of modern physics, but what is not discussed is the speed of two photons during the very moment of a photon-photon collision. How can photons move during a collision? Or, assumea photon is reflected by a mirror; to do so it must collide with the building blocks of the mirror, yet how can it be moving during the very collision point? Also, modern physics assumes mass can be created in a photon-photon collision. We suggest this mass is the Planck mass particle and that it only lasts one Planck time, so when two photons collide, we will claim they must stand still for the direct observer. That is, we suggest thatthe speed of the Planck mass particle is always zero, but that this zero-velocity can only last for one Planck time. That it only lasts one Planck time means it will not break with the relativity principle or Lorenz symmetry, or at least what we can call weak Lorentz symmetry. We will show that the missing Plank mass particle is the very collision point between two photons, and that this is fully in line with predictions in other researchers’ findings in relation to the possible photon mass. This new view seems to solve the missing mass-gap, and seems able to unify gravity with quantum mechanics. This again seems to unify photons with mass, because one of the long-outstanding questions in physics is whether photons have mass or not. In addition, we showhow to find, in a very simple way directly from gravitational observations, lp/tp= cg = c, which is the upper speed limit (the speed of light and gravity) independent of any knowledge of G or ~ or c.

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15

Zhang, Wang-Rui, Tao Shui, Yi-Lou Liu, Ning Ji et Wen-Xing Yang. « Photon routing based on non-chiral interaction between atoms and waveguides ». Laser Physics Letters 19, n^o 1 (30 novembre 2021) : 015203. http://dx.doi.org/10.1088/1612-202x/ac3a0b.

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Abstract The photon router plays an essential role in the optical quantum network. However, conventional routers generally couple photons chirally into waveguides to achieve complete transmission from the input port to the required port. Here, we use non-chiral photon-atom interactions for targeted routing. The system consists of two V-type three-level atoms and two parallel waveguides. In addition, the two atoms are driven by external coherent fields, respectively. With a real-space Hamiltonian, the probability of photon transmitted to four ports can be obtained. The study shows that a single photon input from the left port of the waveguide-a can be deterministically transferred to any of the four ports of the two waveguides by adjusting the detuning of the atom and the driving field on the atom, as well as the distance between the two atoms.

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Walborn, S. P., M. P. Almeida, P. H. Souto Ribeiro et C. H. Monken. « Quantum information processing with hyperentangled photon states ». Quantum Information and Computation 6, n^o 4&5 (juillet 2006) : 336–50. http://dx.doi.org/10.26421/qic6.4-5-3.

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We discuss quantum information processing with hyperentangled photon states - states entangled in multiple degrees of freedom. Using an additional entangled degree of freedom as an ancilla space, it has been shown that it is possible to perform efficient Bell-state measurements. We briefly review these results and present a novel deterministic quantum key distribution protocol based on Bell-state measurements of hyperentangled photons. In addition, we propose a scheme for a probabilistic controlled-not gate which operates with a 50% success probability. We also show that despite its probabilistic nature, the controlled-not gate can be used for an efficient, nonlocal demonstration of the Deutsch algorithm using two separate photons.

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Sherniyozov, A., et Sh Payziyev. « FOCAL SPOT STRUCTURE OF FRESNEL LENS AND ITS HOMOGENIZATION ». «Узбекский физический журнал» 21, n^o 4 (21 août 2019) : 245–49. http://dx.doi.org/10.52304/.v21i4.113.

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Using statistical Monte-Carlo photon-tracing method, we numerically studied focal spot structure of flat Fresnel lens. It has been shown that due to dispersion effect, focal spot structure changes considerably. In addition, we demonstrated homogenization of strongly focused photons. Rectangular prism can be applied to achieve the homogenization.

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Zhang, Qi, Yitong Sun, Jianshu Xue et Lihui Bai. « Distant Magnon-Magnon Coupling Mediated by Nonresonant Photon ». Symmetry 15, n^o 2 (15 février 2023) : 518. http://dx.doi.org/10.3390/sym15020518.

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In this paper, we theoretically and experimentally study the distant magnon-magnon coupling mediated by nonresonant photons. We establish a magnon-photon-magnon coupling model for two CrCl3 crystals spacial separated on a microstrip line. By changing the phase difference of the samples from 0 to π in order to manipulate the distant magnons from coherent coupling to dissipative coupling, our coupling model predicts that the dispersion is tunable from a level repulsion to a level attraction. In addition, we experimentally demonstrate that two spacial separated CrCl3 crystals over a distance of 1.2 cm couple each other indirectly via the microwave photons on the microstrip line. Our works for the distant magnon-magnon coupling mediated by nonresonant photons might provide new sight into long-distant information transmission.

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Hasegawa, Takayuki. « Characteristics of Coherent Optical Phonons in a Hexagonal YMnO3 Thin Film ». Applied Sciences 9, n^o 4 (18 février 2019) : 704. http://dx.doi.org/10.3390/app9040704.

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This paper reviews our recent study on a coherent optical phonon in a hexagonal YMnO3 thin film together with related optical studies in hexagonal RMnO3 (R = Y, Lu, Ho) compounds. Coherent phonons have been observed in RMnO3 compounds by pump-probe spectroscopy with subpicosecond laser pulses, whereas the observation of coherent optical phonons was reported only in LuMnO3. Recently, we succeeded in the observation of the coherent optical phonon in a YMnO3 thin film. The generation process of the coherent optical phonon is assigned to a displacive mechanism, which is identical to that in LuMnO3. The coherent optical phonon is observed in the temperature range from 10 K to room temperature, while the oscillation intensity strongly decreases as the temperature increases to the Néel temperature of ~70 K from a lower temperature range. It is interesting that the temperature dependence is largely different from that in LuMnO3. We describe that the result can be qualitatively explained by the property of an isostructural transition around the Néel temperature in RMnO3 compounds. In addition, we briefly discuss ultrafast incoherent responses of excited electronic states from the viewpoint of the excitation photon energy of laser pulses.

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Sun, Quan-Hai, et Guo-Zhu Pan. « Polarization entanglement distillation through local filtering operations ». International Journal of Quantum Information 16, n^o 04 (juin 2018) : 1850035. http://dx.doi.org/10.1142/s0219749918500351.

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An entanglement distillation scheme is proposed for an amplitude-damped polarization-entangled photon states via local filtering operations. The local filtering operations, i.e. positive operator-valued measure, on photons are realized by a series of Brewster window pairs. The entanglement of the survived photon pairs in the scheme will be much larger than that of the initial ones. In this sense, this distillation scheme is better than the currently existing entanglement protection scheme, where only the entanglement decaying time is prolonged and the entanglement is not enhanced at all. In addition, this scheme is simple and feasible within the current linear optical techniques.

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Bencheikh, Mohamed, Abdelmajid Maghnouj et Jaouad Tajmouati. « Monte Carlo-based analysis of the photon beam fluence with air gap thickness between Linac head exit window and patient’s skin in radiotherapy treatments ». Nuclear Physics and Atomic Energy 21, n^o 3 (25 septembre 2020) : 275–80. http://dx.doi.org/10.15407/jnpae2020.03.275.

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Linear accelerators (Linac) are used in radiation therapy treatment and its technology improvement ensures high dosimetry quality that should be conserved for high radiotherapy efficiency. However, does the air gap between the exit window of Linac head and patient’s skin alters the physical properties of the photon beam? The objective of this study is to assess the physical properties changes of photon beam fluence according to air gap thickness under the Linac head. The air gap under the Linac head is the last material in the photon beam path; it induces alterations in the beam quality before reaching the patient’s skin. The Varian Clinac 2100 head and the air gap up to the phantom surface are modelled using Monte Carlo BEAMnrc code; the nominal beam energy is 6 MV. The BEAMDP code is used to extract the photon fluence. The photon beam fluence is affected by the air gap under Linac head and decreases by six times due to the photon beam attenuation with air gap thickness; in addition to increasing of beam contamination by scattered photons and electrons. Thus, the air gap induces the beam quality deterioration which is evaluated in terms of photon fluence with air gap thickness. To remove the particles contaminations and conserve integrally the photon beam quality, the number of the photon interactions with air atoms should be as low as possible under Linac head up to patient’s skin and ensure a higher quality of the radiotherapy treatment of deep tumour.

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Albicocco, P., R. Assiro, F. Bossi, P. Branchini, B. Buonomo, V. Capirossi, E. Capitolo et al. « Commissioning of the PADME experiment with a positron beam ». Journal of Instrumentation 17, n^o 08 (1 août 2022) : P08032. http://dx.doi.org/10.1088/1748-0221/17/08/p08032.

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Abstract The PADME experiment is designed to search for a hypothetical dark photon A' produced in positron-electron annihilation using a bunched positron beam at the Beam Test Facility of the INFN Laboratori Nazionali di Frascati. The expected sensitivity to the A' -photon mixing parameter ϵ is 10-3, for A' mass ≤ 23.5 MeV/c 2 after collecting ∼ 1013 positrons-on-target. This paper presents the PADME detector status after commissioning in July 2019. In addition, the software algorithms employed to reconstruct physics objects, such as photons and charged particles, and the calibration procedures adopted are illustrated in detail. The results show that the experimental apparatus reaches the design performance, and is able to identify and measure standard electromagnetic processes, such as positron bremsstrahlung and electron-positron annihilation into two photons.

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Lu, Dao-Ming. « Superposition of Photon Subtraction and Photon Addition Excited Squeezed Thermal State and its Wigner Function ». International Journal of Theoretical Physics 56, n^o 11 (31 août 2017) : 3514–24. http://dx.doi.org/10.1007/s10773-017-3516-2.

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Makarov, N. P., A. K. Popov et V. P. Timofeev. « Influence of absorption on resonant four-photon frequency addition ». Soviet Journal of Quantum Electronics 18, n^o 4 (30 avril 1988) : 483–89. http://dx.doi.org/10.1070/qe1988v018n04abeh011770.

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Yuan, Hong-Chun, Xue-Xiang Xu, Jian-Wen Cai, Ye-Jun Xu et Xiang-Guo Meng. « Induced States from Coherent State via Photon-Addition Operations ». International Journal of Theoretical Physics 58, n^o 6 (22 mars 2019) : 1908–26. http://dx.doi.org/10.1007/s10773-019-04086-8.

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König, Karsten. « Two-Photon near Infrared Excitation in Living Cells ». Journal of Near Infrared Spectroscopy 5, n^o 1 (janvier 1997) : 27–34. http://dx.doi.org/10.1255/jnirs.97.

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Non-linear effects due to two-photon near infrared (NIR) excitation of endogenous and exogenous cellular chromophores allow novel techniques in tissue, cell and biomolecule diagnostics, as well as in intracellular micromanipulation (e.g. intracellular photochemistry). Two-photon NIR excitation may also result in cell damage effects. The high photon intensities (1024 photons cm−2 s−1) required for non-resonant two-photon excitation can be achieved by diffraction-limited focusing of continuous wave (cw) laser beams (cw microbeams) with powers in the mW range. For example, NIR traps (“laser tweezers”) used as force transducers and micromanipulation tools in cellular and molecular biology are sources of two-photon excitation. NIR traps can induce two-photon excited visible fluorescence and, in the case of <800 nm-traps, UVA-like cell damage. Multimode cw microbeams may enhance non-linear effects due to longitudinal mode-beating. To perform high scan rate two-photon fluorescence imaging, the application of ultrashort laser pulses of moderate peak power but low average power (pulsed microbeams) is required. In NIR femtosecond microscopes, non-destructive imaging of two-photon excited fluorophores in various human and culture cells was demonstrated for <2 mW average powers, <200 mW peak powers and 400 GW cm−2 intensities (700–800 nm, ∼150 fs, ∼100 MHz). However, higher average power levels may result in failed cell reproduction and cell death due to intracellular optical breakdown. In addition, destructive transient local heating and μN force generation may occur.

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Duc, T. M., T. Q. Dat et H. S. Chuong. « Quantum entanglement and teleportation in superposition of multiple-photon-added two-mode squeezed vacuum state ». International Journal of Modern Physics B 34, n^o 25 (15 septembre 2020) : 2050223. http://dx.doi.org/10.1142/s0217979220502239.

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In this paper, a new state called superposition of multiple-photon-added two-mode squeezed vacuum state (SMPA-TMSVS) is introduced by adding the multiple photons to both modes of a two-mode squeezed vacuum state (TMSVS). We explicitly investigate the degree of quantum entanglement, the Einstein–Podolsky–Rosen (EPR) correlation and the quantum steering in the SMPA-TMSVS. The results show in the SMPA-TMSVS that the degree of entanglement and the EPR correlation can be enhanced by nonlocal adding photons to a TMSVS. The quantum steering appears in the SMPA-TMSVS in case the superposition of single-photon addition [Formula: see text], in which mode [Formula: see text] can steer mode [Formula: see text]. By using the SMPA-TMSVS as an entangled resource, the quantum teleportation process is studied in detail based on the Vaidman–Braunstein–Kimble (VBK) protocol.

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Denk, Winfried. « Multi-Photon Microscopy, High Resolution Imaging Deep in Strongly Scattering Specimens ». Microscopy and Microanalysis 3, S2 (août 1997) : 301–2. http://dx.doi.org/10.1017/s1431927600008394.

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Imaging small structures substantially below the tissue surface in living specimens poses special challenges mainly because light is scattered by ever present refractive index inhomogeneities. Confocal microscoy removes the blurring caused by scattered and out-of-focus light but does so only at the expense of photodynamic damage that is often unacceptable when observing live specimens.Multi-photon absorption microscopy[l] solves these problems because excitation is virtually limited to the focal plane. Out-of-focus photobleaching and photodamage are therefore eliminated. In scattering samples substantial improvements accrue even for the focal plane because, different from confocal microscopy, where only ballistic fluorescenc photons can be used, in the multi-photon microscope scattered photons can be utilized in addition [2-4], provided whole-field detection is used[5].Many questions in the study of the nervous system require the investigation of intact portions of neural tissue in order to preserve the multiply branched processes of neurons, often extending over hundreds of microns, together with the local nervous circuitry.

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Saleh, Gh, M. J. Faraji, R. Alizadeh et A. Dalili. « A New Explanation for the Color Variety of Photons ». MATEC Web of Conferences 186 (2018) : 01003. http://dx.doi.org/10.1051/matecconf/201818601003.

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This new explanation is based on Wave-Particle Duality and Newtonian Laws and represents a unique definition of a three-dimensional motion for the photon, whose dual behavior is partly explained by the double-slit experiment of Thomas Young, who represents the photon's motion as a wave, and by the Photoelectric effect, in which the photon is considered as a particle. However, for scientists, the photon's true motion is unclear. In this article, we define a new type of motion for photons to solve both this ambiguity and the difficulty of presenting a three-dimensional trajectory for the photon's motion, and present a new formula to calculate its energy. In addition, because we believe in the helical motion of photons, where r is the gyroradius, we believe that their color is an effect of the order of magnitude of r. We present real examples that prove our energy formula.

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Shao, Yabin, Chen Chen, Qing He, Wenzhi Wu, Chensha Li et Yachen Gao. « Broadband Visible Nonlinear Absorption and Ultrafast Dynamics of the Ti3C2 Nanosheet ». Nanomaterials 10, n^o 12 (17 décembre 2020) : 2544. http://dx.doi.org/10.3390/nano10122544.

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The Ti3C2 nanosheet, as a new two-dimensional (2D) group, has been found to have attractive characteristics as material for electromagnetic shielding and energy storage. In this study, the nonlinear broadband absorption and ultrafast dynamics of the Ti3C2 nanosheet were investigated using nanosecond open-aperture Z-scan and transient absorption techniques. The mechanism of two-photon absorption (TPA) was revealed in the visible region (475–700 nm). At lower incident energies, nonlinear absorption could not happen. When the laser energy increased to 0.64 GW/cm2, electrons in the valence band could absorb two photons and jump to the conduction band, with TPA occurring, which meant that the sample exhibited reverse saturable absorption (RSA). In addition, when transient absorption was used to investigate the ultrafast carrier dynamics of the sample, it demonstrated that the relaxation contains a fast decay component and a slow one, which are obtained from electron–phonon and phonon–phonon interactions, respectively. Moreover, with the increasing pump fluence, the fast decay lifetime τ1 increased from 3.9 to 4.5 ps, and the slow one τ2 increased from 11.1 to 13.2 ps. These results show that the Ti3C2 nanosheet has potential applications in broadband optical limiters.

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Li, Chang, Mingxin Chen, Fen Li, Xiaoxiang Sun, Zhuoliang Yu, Jiayou Tao, Zhijun Zou, Gaohua Liao et Jianjun Zhang. « Simulation of Light-Trapping Characteristics of Self-Assembled Nano-Ridges in Ternary Organic Film ». Coatings 12, n^o 9 (15 septembre 2022) : 1340. http://dx.doi.org/10.3390/coatings12091340.

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The presence of self-assembled nano-ridged (SANR) structures in PTB7-Th:PC70BM:PC60BM ternary organic blend film with the specific component ratio was experimentally clarified, and the light-trapping effect of the SANR structures was demonstrated. On this basis, the light-trapping characteristics of the PTB7-Th:PC70BM:PC60BM ternary blend film with the SANR structures were investigated by using the finite-difference time-domain (FDTD) algorithm. The results showed that the SANR structures have a light-trapping effect, which can effectively reduce the transmittance and reflectance of the incident photons at the specific wavelengths and thus exhibit stronger photon absorption, especially for the photons in the wavelength range of 550–650 nm. The light-trapping effect of the SANR structures does not depend on the direction of photon incidence, and the active layer traps the photons incident from both its top and bottom. The dimensional variation of the SANR has a significant effect on the light-trapping characteristics of the active layer, and the effect caused by the height variation is overwhelmingly superior compared with that of the width variation. In addition, the higher the density of the SANR, the more significant the light-trapping effect of the active layer. This work provides a theoretical basis for the further experimental enhancement of the photon absorption capacity of the PTB7-Th:PC70BM:PC60BM active layer with SANR structures.

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Khudyakov, Dmitry S. « Capabilities of image sensors with a photonic avalanche diode ». Analysis and data processing systems, n^o 2 (28 juin 2022) : 69–80. http://dx.doi.org/10.17212/2782-2001-2022-2-69-80.

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In many fields of science and technology there is a need to record fast running processes and phenomena, often occurring in low light conditions. In such cases, there is a need to use highly sensitive image sensors. Such sensors can be constructed on the basis of photon avalanche diodes capable of capturing even single photons. However, creating this type of sensor with high performance, in particular, with high resolution, presents a number of technological challenges, as they are more complex than traditional CMOS (Complementary Metal–Oxide–Semiconductor) and CCD (Charge-Coupled Device) sensors. Using recent advances and new circuitry, Canon created the first megapixel image sensor with a photon avalanche diode (Single Photon Avalanche Diode, SPAD). In this article, in addition to general issues related to image sensors with photon avalanche diode, the design, operation, characteristics, features and possible applications of Canon’s SPAD megapixel sensor are discussed. In particular, the methods of photon counting and time-of-flight are discussed, as well as the dynamic range of the sensor, the possibilities of sensor application for imaging in the infrared range, and the prospects for wide application of SPAD sensors in the near future. As a result, it can be noted that in addition to direct use for obtaining high-quality 2D-images of fast processes running in low light conditions, such a sensor can be used for taking images in the infrared range, to obtain 3D-images for xReality, measuring the distance to objects, obtaining a depth map, as well as in areas of science and technology that are new for such devices, including, for example, quantum computing.

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Qinghua, HE. « Measuring space-time properties of baryon resonances around 1 GeV using intensity correlations ». Journal of Physics : Conference Series 1643, n^o 1 (1 décembre 2020) : 012010. http://dx.doi.org/10.1088/1742-6596/1643/1/012010.

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Abstract We measured the Δ(1232) radius using Bose-Einstein correlations (BEC) between two neutral pions from photo-production off a hydrogen/deuterium target at the incident photon energies around 1 GeV. The experiment was carried out at Research Center for Electron Photon Science (ELPH) in Tohoku University with a 4π electromagnetic calorimeter complex, named FOREST. For low-multiplicity BEC measurements, we developed an event mixing technique by introducing additional mixing constraints to delicately reduce the effect of other non-BEC correlations arising from global conservation law and resonance decays. In addition, a new BEC observing model was established to extract radius information from BEC effects in the presence of resonance decays.

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Gronberg, Jeffrey. « The Photon Collider ». Reviews of Accelerator Science and Technology 07 (janvier 2014) : 161–75. http://dx.doi.org/10.1142/s1793626814300084.

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The idea of converting an electron linear collider into a photon–photon collider through the addition of high power lasers was put forward in the early 1980s. Progress in the field of high average power, short pulse lasers has brought the state of the art within striking range of what would be required to realize a photon collider. In parallel, the necessary modifications to the detector and accelerator to enable a photon collider have been laid out. The basic concept of the photon collider, the requirements for the laser, and the detector and accelerator impact are reviewed in this article.

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PATHAK, ANIRBAN, et SWAPAN MANDAL. « PHOTON-BUNCHING, PHOTON-ANTIBUNCHING AND NONCLASSICAL PHOTON STATISTICS OF COHERENT LIGHT COUPLED TO A CUBIC NONLINEAR MEDIUM ». Modern Physics Letters B 17, n^o 05n06 (10 mars 2003) : 225–33. http://dx.doi.org/10.1142/s0217984903005123.

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The quantum statistical properties of a single mode of the radiation field, prepared in the coherent state, interacting with a nonlinear medium of inversion symmetry are studied with the help of the usual two photon correlation function for zero time delay. We report the photon antibunching and sub-Poissonian photon statistics in addition to the usual photon bunching and the super-Poissonian photon statistics for an input vacuum field. The manipulation of the phase of input coherent light gives rise to the well known self induced transparency. The possible physical explanations for these events are presented.

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Ramos-Prieto, I., B. M. Rodríguez-Lara et H. M. Moya-Cessa. « Engineering nonlinear coherent states as photon-added and photon-subtracted coherent states ». International Journal of Quantum Information 12, n^o 07n08 (novembre 2014) : 1560005. http://dx.doi.org/10.1142/s0219749915600059.

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We propose a class of nonlinear coherent states which are experimentally feasible in cavity or ion-trap quantum electrodynamics. These quantum field states arise from a new type of photon addition and subtraction based on London phase operators, also known as Susskind–Glogower operators, that just displaces the mean photon number without scaling the photon distribution.

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Jin, Rui-Bo, Hiroki Oshima, Takumi Yagisawa, Masahiro Yabuno, Shigehito Miki, Fumihiro China, Hirotaka Terai et Ryosuke Shimizu. « Two-photon spectral modulation via temporal manipulation : Quantum optical synthesis of spectral modes from temporal square waves ». Applied Physics Letters 121, n^o 24 (12 décembre 2022) : 244002. http://dx.doi.org/10.1063/5.0111687.

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Precise manipulation of the time–frequency modes of entangled photons is crucial for future quantum science and technologies. Recently, the frequency-domain-quantum-optical-synthesis (FD-QOS) method was demonstrated by creating a superposition of different joint temporal amplitudes: those temporal distributions can be controlled by manipulating the joint spectral amplitude in 2D frequency space via a Fourier optical relation. This FD-QOS method provides an efficient, flexible, and easy-to-control way to precisely modulate the temporal distributions of the entangled photon in an ultrafast region. However, manipulation of only the temporal modes is not sufficient for various applications in quantum information, since spectral modulations are also needed on many occasions. Here, we present a proof-of-concept experiment of two-photon spectral modulation via temporal manipulation of a biphoton wave packet. This protocol, called time-domain-quantum-optical-synthesis (TD-QOS), is achieved by adjusting the relative phases between two joint temporal distributions. In addition, the two-photon joint spectral distributions are characterized by measuring the joint spectral intensities and Hong–Ou–Mandel interferences. The combination of FD-QOS and TD-QOS enables complete control over the biphoton states. Our work would further develop quantum technologies that rely on the time–frequency modes of entangled photons.

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Bian, Fang, XinGe Wu, Shuai Shao, XiangYing Meng et GaoWu Qin. « Effects of impurities on the cooling of photoexcited carriers in La_1−xSr_xCoO_3−δ : A DFT and nonadiabatic molecular dynamics study ». Journal of Applied Physics 133, n^o 6 (14 février 2023) : 065107. http://dx.doi.org/10.1063/5.0137557.

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Photo-carrier relaxation in semiconductors determines their photon-conversion efficiency. Impurities have been proven to play an essential role in improving the efficiency and stability of perovskites. We studied the effects of Sr-doping and O-vacancies on the electronic band structure and photoexcited carrier cooling of perovskite-type LaCoO3 using density functional theory and nonadiabatic molecular dynamics methods. We found that the substitution of Sr2+ for La3+ in LaCoO3 leads to a semiconductor–metal transition, while a stoichiometric oxygen vacancy restores semiconductor properties in La1− xSr xCoO3− δ ( δ = x/6). In addition, the oxygen vacancy basically changes the electronic band structures, and for visible light with low oxygen vacancy intensity, the photo-electron cooling can be reduced fourfold relative to that of pure LaCoO3. We clarify the functions of impurities, Sr-dopants, and O-vacancies in LaCoO3 and find that the average coupling strength between carriers (electrons/holes) and phonons can be used as a descriptor to characterize carrier relaxation, which is of great value for the further development of practical photo-conversion based on perovskites.

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Vormstein, Mario. « Kaon physics at the CERN-SPS ». International Journal of Modern Physics : Conference Series 39 (janvier 2015) : 1560100. http://dx.doi.org/10.1142/s2010194515601003.

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The NA48/2 and NA62 collaborations report on recent results, current status, and prospects of kaon physics at the CERN-SPS. The NA62 collaborations aims to measure the decay [Formula: see text] with an uncertainty of 10% or better. The NA62 detector and preliminary results from a pilot run in 2014 are presented. In addition, recent results of the NA48/2 collaboration are reported. A search for Dark Photons has been performed in [Formula: see text] decays via the kaon decays [Formula: see text] and [Formula: see text]. No dark photon signal was observed and new upper limits on the mixing parameter [Formula: see text] and the dark photon mass were computed. We also report the first observation of the kaon decay [Formula: see text].

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Chen, Xiao-Ting, Lu-Ping Zhang, Shou-Kang Chang, Huan Zhang et Li-Yun Hu. « Continuous-variable quantum key distribution based on photon addition operation* ». Chinese Physics B 30, n^o 6 (1 juin 2021) : 060304. http://dx.doi.org/10.1088/1674-1056/abd931.

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Zhang, Pei, Hong-Rong Li, Hong Gao et Fu-Li Li. « Entanglement distillation from Gaussian input states by coherent photon addition ». Journal of Modern Optics 58, n^o 10 (13 avril 2011) : 835–38. http://dx.doi.org/10.1080/09500340.2011.575241.

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Yuan, Hong-Chun, Xue-Xiang Xu, Jian-Wen Cai et Ye-Jun Xu. « Single-mode squeezed vacuum state orthogonalization via photon-addition operation ». Optik 183 (avril 2019) : 1043–47. http://dx.doi.org/10.1016/j.ijleo.2019.02.120.

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Dat, Tran Quang, et Truong Minh Duc. « Higher-order nonclassical and entanglement properties in photon-added trio coherent state ». Hue University Journal of Science : Natural Science 129, n^o 1B (22 juin 2020) : 49–55. http://dx.doi.org/10.26459/hueuni-jns.v129i1b.5685.

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This paper studies the higher-order nonclassical and entanglement properties in the photon-added trio coherent state (PATCS). We use the criterion of higher-order single-mode antibunching to evaluate the role of the photon addition operation. Furthermore, the general criteria for detection of higher-order three-mode sum squeezing and entanglement features in the PATCS are also investigated. The results show that the photon addition operation to a trio coherent state can enhance the degree of both the higher-order single-mode antibunching and the higher-order three-mode sum squeezing and enlarge the value of the higher-order three-mode entanglement factor in the photon-added trio coherent state. In addition, the manifestation of the single-mode antibunching and the entanglement properties are more obvious with increasing the higher values of orders.

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Wang, Zhen, Hong-chun Yuan et Hong-yi Fan. « Nonclassicality of the photon addition-then-subtraction coherent state and its decoherence in the photon-loss channel ». Journal of the Optical Society of America B 28, n^o 8 (20 juillet 2011) : 1964. http://dx.doi.org/10.1364/josab.28.001964.

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Ruqaya Raad et Mustafa Abdallh. « Surface modification to enhance photo-stability of polymers ». GSC Advanced Research and Reviews 11, n^o 2 (30 mai 2022) : 080–88. http://dx.doi.org/10.30574/gscarr.2022.11.2.0130.

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Photo-degradation is an irreversible alteration in the chemical, mechanical and physical properties of polymers, these alterations are a result of photon absorption from sunlight. UV-light is considered to be the main factor for initiating photo-degradation process of polymers. To extend the lifetime of polymers, their durability, overall minimization of the rate of photo degradation and protection of polymers against environmental factors, stabilizers are introduced to polymers. In addition, since the interaction of the polymer with its environment occurs mainly at the surface of the polymer, therefore surface modification of polymers is used to enhance the UV photo-stabilization. This method can also provide a more durable, weather resistant and photo-stable polymers.

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Humphrey, A., M. Villar-Martín, L. Binette et R. Raj. « Photoionization models for extreme Lyα λ1216 and Hell λ1640 line ratios in quasar halos, and PopIII vs. AGN diagnostics ». Astronomy & ; Astrophysics 621 (20 décembre 2018) : A10. http://dx.doi.org/10.1051/0004-6361/201732007.

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Aims. We explore potential mechanisms to produce extremely high Lyα/HeII flux ratios, or to enhance the observed number of Lyα photons per incident ionizing photon, in extended active galactic nucleus (AGN) photoionized nebulae at high-redshift. Methods. We computed models to simulate, in the low density regime, photoionization of interstellar gas by the radiation field of a luminous AGN. We have explored the impact of ionization parameter, gas metallicity, ionizing spectrum, electron energy distribution, and cloud viewing angle on the relative fluxes of Lyα, HeII and other lines, and on the observed number of Lyα photons per incident ionizing photon. We have compared our model results with recent observations of quasar Lyα halos at z ∼ 3.5. Results. Low ionization parameter, a relatively soft or filtered ionizing spectrum, low gas metallicity, κ-distributed electron energies, or reflection of Lyα photons by neutral hydrogen can all result in significantly enhanced Lyα relative to other lines (≥10%), with log Lyα/HeII reaching values of up to 4.6. In the cases of low gas metallicity, reflection by HI, or a hard or filtered ionizing spectrum, the observed number of Lyα photons per incident ionizing photon is itself significantly enhanced above the nominal Case B value of 0.66 due to collisional excitation, reaching values as high as 5.3 in an “extreme case” model which combines several of these effects. We find that at low gas metallicity (e.g. Z/Z⊙ = 0.1) the production of Lyα photons is predominantly via collisional excitation rather than by recombination. In addition, we find that the collisional excitation of Lyα becomes much more efficient if the ionizing continuum spectrum has been pre-filtered through an optically thin screen of gas closer to the AGN (e.g. by a wide-angle, feedback-driven outflow). We also show that the Lyα and HeII emission line ratios of a sample of previously studied quasars at z ∼ 3.5 are consistent with AGN-photoionization of gas with moderate to low metallicity and/or low ionization parameter, without requiring exotic ionization or excitation mechanisms such as strong line-transfer effects. In addition, we present a set of UV-optical diagnostic diagrams to distinguish between photoionization by Pop III stars and photoionization by an AGN.

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Wei, Xing, et Samuel Kesse. « Heterogeneously Integrated Photonic Chip on Lithium Niobate Thin-Film Waveguide ». Crystals 11, n^o 11 (12 novembre 2021) : 1376. http://dx.doi.org/10.3390/cryst11111376.

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Lithium niobate thin film represents as an ideal material substrate for quantum photonics due to its strong electro-optic effect and high-speed modulation capability. Here, we propose a novel platform which heterogeneously integrates single self-assembled InAs/GaAs quantum dots for a single-photon source on a lithium niobate photonic chip. The InAs/GaAs quantum dots can be transferred to the lithium niobate waveguide via a substrate transfer procedure with nanometer precision and be integrated through van der Waals force. A down-tapered structure is designed and optimized to deliver the photon flux generated from the InAs quantum dots embedded in a GaAs waveguide to the lithium niobate waveguide with an overall efficiency of 42%. In addition, the electro-optical effect is used to tune, and therefore to tune the beam splitting ratio of the integrated lithium niobate directional coupler, which can simultaneously route multiple photons to different spatial modes, and subsequently fan out through grating couplers to achieve single-photon sub-multiplexing. The proposed device opens up novel opportunities for achieving multifunctional hybrid integrated photonic chips.

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Du, Mengfei, Yi Chen, Weitong Li, Linzhi Su, Huangjian Yi, Fengjun Zhao, Kang Li, Lin Wang et Xin Cao. « MSCN-NET : Multi-stage cascade neural network based on attention mechanism for Čerenkov luminescence tomography ». Journal of Applied Physics 132, n^o 17 (7 novembre 2022) : 173104. http://dx.doi.org/10.1063/5.0119787.

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Čerenkov luminescence tomography (CLT) is a highly sensitive and promising technique for three-dimensional non-invasive detection of radiopharmaceuticals in living organisms. However, the severe photon scattering effect causes ill-posedness of the inverse problem, and the results of CLT reconstruction are still unsatisfactory. In this work, a multi-stage cascade neural network is proposed to improve the performance of CLT reconstruction, which is based on the attention mechanism and introduces a special constraint. The network cascades an inverse sub-network (ISN) and a forward sub-network (FSN), where the ISN extrapolates the distribution of internal Čerenkov sources from the surface photon intensity, and the FSN is used to derive the surface photon intensity from the reconstructed Čerenkov source, similar to the transmission process of photons in living organisms. In addition, the FSN further optimizes the reconstruction results of the ISN. To evaluate the performance of our proposed method, numerical simulation experiments and in vivo experiments were carried out. The results show that compared with the existing methods, this method can achieve superior performance in terms of location accuracy and shape recovery capability.

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Khankook, Atiyeh Ebrahimi, Hashem Miri Hakimabad et Laleh Rafat Motavalli. « A feasibility study on the use of phantoms with statistical lung masses for determining the uncertainty in the dose absorbed by the lung from broad beams of incident photons and neutrons ». Journal of Radiation Research 58, n^o 3 (11 janvier 2017) : 313–28. http://dx.doi.org/10.1093/jrr/rrw118.

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Abstract Computational models of the human body have gradually become crucial in the evaluation of doses absorbed by organs. However, individuals may differ considerably in terms of organ size and shape. In this study, the authors sought to determine the energy-dependent standard deviations due to lung size of the dose absorbed by the lung during external photon and neutron beam exposures. One hundred lungs with different masses were prepared and located in an adult male International Commission on Radiological Protection (ICRP) reference phantom. Calculations were performed using the Monte Carlo N-particle code version 5 (MCNP5). Variation in the lung mass caused great uncertainty: ~90% for low-energy broad parallel photon beams. However, for high-energy photons, the lung-absorbed dose dependency on the anatomical variation was reduced to <1%. In addition, the results obtained indicated that the discrepancy in the lung-absorbed dose varied from 0.6% to 8% for neutron beam exposure. Consequently, the relationship between absorbed dose and organ volume was found to be significant for low-energy photon sources, whereas for higher energy photon sources the organ-absorbed dose was independent of the organ volume. In the case of neutron beam exposure, the maximum discrepancy (of 8%) occurred in the energy range between 0.1 and 5 MeV.

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Naderi, M. H., M. Soltanolkotabi et R. Roknizadeh. « On a family of photon-added deformed coherent states associated with two-parameter deformed boson oscillator algebra ». Canadian Journal of Physics 82, n^o 8 (1 août 2004) : 623–46. http://dx.doi.org/10.1139/p04-031.

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By introducing a generalization of the (p, q)-deformed boson oscillator algebra, we establish a two-parameter deformed oscillator algebra in an infinite-dimensional subspace of the Hilbert space of a harmonic oscillator without first finite Fock states. We construct the associated coherent states, which can be interpreted as photon-added deformed states. In addition to the mathematical characteristics, the quantum statistical properties of these states are discussed in detail analytically and numerically in the context of conventional as well as deformed quantum optics. Particularly, we find that for conventional (nondeformed) photons the states may be quadrature squeezed in both cases Q = pq < 1, Q = pq > 1 and their photon number statistics exhibits a transition from sub-Poissonian to super-Poissonian for Q < 1 whereas for Q > 1 they are always sub-Poissonian. On the other hand, for deformed photons, the states are sub-Poissonian for Q > 1 and no quadrature squeezing occurs while for Q < 1 they show super-Poissonian behavior and there is a simultaneous squeezing in both field quadratures.PACS Nos.: 42.50.Ar, 03.65.w

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